Upgrading of recycled plastics by restabilization—an overview

Thermal, mechanical and permeation properties of gamma-irradiated multilayer food packaging films containing a buried layer of recycled low-density polyethylene

“…The material value of plastics intended for recycling is influenced by their origin and history (Pospisil et al, 1995). In general, melt processing, usually employed as a step of plastics recycling process, may introduce oxidative as well as thermomechanical degradation of (Incarnato et al, 1998;Tzankova Dintcheva et al, 1997).…”

Mechanical recycling of postused high-density polyethylene crates using the restabilization technique. I. Influence of reprocessing

“…4,10,12,14,15 In addition, as a rule, polymers are stabilized only for their first life, but this original stabilization is generally insufficient for reprocessing and second life application. 8,9,11,16 Therefore, quality improvement of the recycled plastics becomes the key issue. To achieve upgrading of recycled plastics, not only sophisticated cleaning and separation is needed, but also material properties must be optimized.…”

“…Among the material recycling technologies that have already been developed, the remelting technique; that is, reprocessing in the melt phase, remains the most effective, popular, economical and easily applicable method. [5][6][7][8][9] Nevertheless, this technology often leads to degraded products of inferior value, because plastics, as organic materials, are subjected to undesirable chemical reactions during their previous processing steps and service life, mainly caused by oxidation and photo-oxidation. These chemical reactions lead to irreversible changes in the polymer structure, affecting the physical properties and the quality of the polymer.…”

Natural Ageing of Automotive Polymer Components: Characterisation of New and Used Poly(propylene) based Car Bumpers

“…[1,2] The aim is to use recycled material to fully replace virgin polymer, making the polymer life virtually endless. However, this approach opens a fascinating challenge to the polymer researchers, who have to discover the chemical reasons for the impairment of the mechanical properties of car items during their useful life and then suggest how to improve the recycled material performances up to the original level.…”